Tests and diagnosis

By Mayo Clinic Staff

When you see a doctor because you're having trouble getting your partner pregnant, he or she will try to determine the underlying cause. Even if your doctor thinks low sperm count is the problem, you and your partner may both need tests to rule out other causes of infertility and to look for any underlying health problems. Testing and diagnosis may involve the following:

General physical examination and medical history

This includes examination of your genitals and questions about any inherited conditions, chronic health problems, illnesses, injuries or surgeries that could affect fertility. Your doctor may also ask about your sexual habits and your sexual development.

Semen analysis

A low sperm count is diagnosed as part of a semen analysis test. Sperm count is generally determined by examining semen under a microscope to see how many sperm appear within squares on a grid pattern. In some cases, a computer may be used to measure sperm count.

To collect a semen sample, your doctor will have you masturbate and ejaculate into a special container. It's also possible to collect sperm for examination during intercourse, using a special condom. Sperm counts often fluctuate. In most cases, several semen analysis tests are done over a period of time to ensure accurate results.

New sperm are produced continually in the testicles and take about 40 to 76 days to mature. So, a current semen analysis reflects your environment over the past 2.5 months. Any positive changes you've made won't show up for a period of several months.

One of the most common causes of low sperm count is incomplete or improper collection of a sperm sample. Most doctors will check two or more semen samples over time to ensure consistency between samples. To ensure accuracy in a collection, your doctor will want to:

  • Ensure all of your semen makes it into the collection cup or collection condom when you ejaculate
  • Wait at least three months after you've recovered from an illness or stressful event to collect a sperm sample
  • Have you abstain from ejaculating for at least two but no longer than seven times before collecting a sample
  • Make sure a second sample is collected at least seven days after the first
  • Have you avoid the use of lubricants because these products can affect sperm motility

Semen analysis results

Normal sperm densities range from 15 million to greater than 200 million sperm per milliliter of semen. You are considered to have a low sperm count if you have fewer than 15 million sperm per milliliter or less than 39 million sperm total per ejaculate. Your chance of getting your partner pregnant decreases with decreasing sperm counts. Some men have no sperm in their semen at all. This is known as azoospermia (ay-zoh-uh-SPUR-me-uh).

There are many factors involved in reproduction, and the number of sperm in your semen is only one. Some men with low sperm counts successfully father children. Likewise, some men with normal sperm counts are unable to father children. Even if you have enough sperm, you're much more likely to get your partner pregnant if at least half of your sperm have a normal shape (morphology) and show normal forward movement (motility).

Other tests

Depending on initial findings, your doctor may recommend additional tests to look for the cause of your low sperm count and other possible causes of male infertility. These can include:

  • Scrotal ultrasound. This test uses high-frequency sound waves to look at the testicles and supporting structures.
  • Transrectal ultrasound. A small lubricated wand is inserted into your rectum to check your prostate, and for blockages of the tubes that carry semen (ejaculatory ducts and seminal vesicles).
  • Hormone testing. Your doctor may recommend a blood test to determine the level of hormones produced by the pituitary, hypothalamus and testicles, which play a key role in sexual development and sperm production.
  • Post-ejaculation urinalysis. Sperm in your urine can indicate your sperm are traveling backward into the bladder instead of out your penis during ejaculation (retrograde ejaculation).
  • Genetic tests. When sperm concentration is extremely low, genetic causes could be involved. A blood test can reveal whether there are subtle changes in the Y chromosome — signs of a genetic abnormality. Genetic testing may also be ordered to diagnose various congenital or inherited syndromes.
  • Testicular biopsy. This test involves removing samples from the testicle with a needle. It may be used if your semen analysis shows no sperm at all. The results of the testicular biopsy will tell if sperm production is normal. If it is, your problem is likely caused by a blockage or another problem with sperm transport.
  • Anti-sperm antibody tests. These tests are used to check for immune cells (antibodies) that attack sperm and affect their ability to function.
  • Specialized sperm function tests. A number of tests can be used to evaluate how well your sperm survive after ejaculation, how well they can penetrate an egg and whether there's any problem attaching to the egg. If you do have a low sperm count, having healthy sperm can be an important factor in male fertility.
Sep. 22, 2012